Scaling while conserving ration - filepicker.io

Upon using the convert method, I would like to be able to transform a landscape or portrait image given the height and width specify without altering the ratio.
From the documentation, the 'clip' options act as follow:
'clip': Resizes the image to fit within the specified parameters without distorting, cropping, or changing the aspect ratio
If I have a 200x50 image and I want a 150x150 result, this would result in a 150x37px resized image with its ratio identical to the original's.
If I have a 100x50 image and I want a 150x150 result, this would result in a 150x75px resized image with its ratio identical to the original's.
'crop': Resizes the image to fit the specified parameters exactly by removing any parts of the image that don't fit within the
boundaries
If I have a 200x50 image and I want a 150x150 result, this would result in a 150x37px cropped image.
'scale': Resizes the image to fit the specified parameters exactly by scaling the image to the desired size
If I have a 200x50 image and I want a 150x150 result, this would result in a 150x150px resized image where the ratio has been altered to fit.
'max': Resizes the image to fit within the parameters, but as opposed to 'clip' will not scale the image if the image is smaller
than the output size
Same output as in 'clip' except that if I have a 100x50 image and I want a 150x150 result, this would result in a 100x50px resized image with its ratio identical to the original's.
What I would like to have is the ability to make an image conserve its ratio and be of the required dimension (with vertical and horizontal centering if need be). It would result in an image that is not distorted nor clipped.
I understand there are some trickiness to the task as you have to determine what color do you fill the space with (see ImageMagick doc about space filling).
Any insight would be great, hope it is not too much of an edge case.

Take a look at this set of examples in the ImageMagick documentation:
http://www.imagemagick.org/Usage/thumbnails/#square

We don't currently offer the ability to "fill" empty parts of the image with a background color, so do not support this use case. We are looking at adding it in the near term, and will update you when this is added.

Related

Add an image to the map and make sure aspect ratio is correct

I have tried adding an image to Leaflet using ImageOverlay, see for example the following code:
imageBounds = [[40.712216, -74.22655], [40.773941, -74.12544]];
var ol = L.imageOverlay(imageUrl, imageBounds).addTo(mymap);
Now the image is added, but I would like to use the aspect ratio of the image and I would prefer to actually set the image's center point instead of the bounds. Is this at all possible?
Size of the image is not that critical, lets say I want the width to be set to 60% of the current visible area of the map, I then want the height to be calculated so that the aspect ratio of the image is kept.
Problem is I am not sure I can just translate between latitude/longitude and x/y.
Is it correct to assume that the aspect ratio longitude/latitude is the same as for x/y if the map is quite zoomed in?
Is there an easier way to do this maybe?

Resizing command changes image shape

I have to resize image i.e if its dimension is 3456x5184 to 700X700 as my code needs image with less number of pixels otherwise it takes too much time to give results.So, when I use imresize command it changes the dimensions of image but at the same time it changes the shape of image i.e the circle in image which I also need to detect looks like oval instead of being cirle. I need your suggestions to resolve this problem. I am really grateful to you people.
Resizing images is done by either subsampling (to get smaller images) or some kind of interpolation (to get larger images)
Input is either a factor or a final dimension for width and height.
The only way to fit a rectangle into a square by simply resizing it is to use different scales for width and height. Which of course will yield in a distorted image.
To achieve what you want you can either crop a 700x700 region from your image or resize image using the same factor for with and height. Then you can fit the larger dimension into 700 and fill the rest around the other dimension with black or whatever you prefer.

Advanced image scaling in JasperReports

I need to include many images of unknown origin in a report. I have no idea what the images might be: portrait or landscape fotos, large or small, or even something with an atypical shape, like a 400x80 logo.
I'd like to scale down images with the following rule: proportionally downscale until the larger side is 200. And resulting image shouldn't take more space than needed (i.e. 1000x600 should be downscaled to 200x120, not to 200x200), so that there are no unneeded blank margins around non-square images.
Is what I need possible with JasperReports?
EDIT:
To clarify: "real size" mode is almost what I need. However, I don't see a way to limit height of resulting image. As a result, if the image I want to print is a portrait foto (or has even larger height compared to width), generated PDF looks ugly; in this case I would prefer to somehow downscale it to a smaller width.
I solved the Problem of resizing images of various sizes to a fixed size with "RetainShape" by writing an ImageResizer, based on the idea of the ImageTransformer from https://stackoverflow.com/a/39320863/8957103 , using https://github.com/rkalla/imgscalr for scaling the image.

How to re size a too big image into small by keeping original values

I have an gray scale image of size <2559x3105 uint16>. when I try to open this image, I get warning that it is too big. I have tried imresize() function to make it small<512x512 uint8> in size. When I plot the original image and re-sized image, the intensity gets decreased after re-sizing. I want to re-size original image without changing in its pixel values. Is there any solution?
If you would like to keep your final image as uint8, I think you would be needed to first convert the uint16 image to uint8 image using im2uint8 -
uint8_image = im2uint8(uint16_image);
Then you may apply imresize on uint8_image.
But, if you don't want your final image to be of uint8 type, you can directly use imresize and it would keep the datatype, i.e. the resized image would be of uint16 type.
Read the docs and use the nearest neighbor method. That is,
resized = imresize(original, scale, 'nearest')
This will not use interpolated values. The downside is of course that edges might be jagged.
It sounds like your 16-bit image uses linear codes while the resulting 8-bit image needs to be gamma corrected. If this is the case you can use imadjust with a gamma parameter of 1/2.2 to produce the brighter image.
Do you get the warning when you display it with imshow? Does it say something like "Image to large to fit the screen, resizing to xx%"? If so, then you can simply ignore the warning. Otherwise, you can can set the 'InitialMagnification' parameter of imshow to resize the figure, but not the image itself.

Difference between stretching and scaling an image

Can anybody please tell me what is the exact difference between stretching and scaling an image? Because you can anyway set the size of image and imageView both to match your requirements.
It depends on how you define stretching, but I would divide scaling into two distinct options based on whether or not the aspect ratio is preserved. Often it is desired to preserve the aspect ratio when scaling an image.
I would consider an increase in one dimension, but not proportionally in the other to be a "stretch". Similarly, a decrease in one dimension, but not proportionally in the other would be a "squash".
You may find this Daring Fireball post interesting.
Stretching sounds like showing small size (10x10) image at (100x100) or (100x10). so some times it gets pix-elated.
And scaling means to show a image to different size either small or big with maintaining its aspect ratio (programmetically), so it will look not improper, because when you stretch to different aspect ratio then some objects in image gets improper visibility.
Stretching (in iphone IB) means '9-slice scaling', scaling means just scaling.
When stretching you can determine which part of the image may be used for stretching and which part may not. For example when you have a rounded square, you do not want the roundings to stretch, especially when you're only stretching horizontally or vertically.
You indicate that you only want to use the middle pixel to stretch by (in IB) setting the X & Y values to 0.50 (half way) and the width & height values to 0.00 (minimum amount of pixels)
Lookup contentStretch in the docs for more info
when you don,t keep the congruence of your image, you see the image incongruous and height and width of your image is not suitable for showing. for resolving this issue you can multiply your image's width and height to to a constant coefficient.
Stretching and scaling don't mean anything different except maybe in connotation.
Is there a particular piece of text somewhere that you are trying to understand? Maybe we can help with that.
stretching image is stretching the size of a small image.
on the other hand scaling of image is scaling the image accoring the the viewport's width and viewport's height....
scaling can be done by small as well as large image.
you should take a good quality image and then should scale it
sprite.setscale(x,y);